Abstract
Dissolution kinetics of zinc oxide (ZnO) powders used as feed additives for supplementation in diet of animals is studied in relation to the powder physicochemical characteristics. The fundamental issue of discrimination of reaction-limited or diffusion-limited dissolution into a stirred liquid medium is addressed. Relationships between dissolution kinetics and physicochemical properties are investigated for a set of 34 ZnO samples of various origins. A principal component analysis allows sorting ZnO samples in three clusters having different physicochemical properties. A correlation analysis discloses the most relevant physicochemical characteristics affecting dissolution: density, agglomerate size and specific surface area. Coarse particles dissolve in a reaction-limited process according to their specific surface area. Fine aggregated particles dissolve in 2 steps: reaction-limited dissolution at the surface of ZnO primary particles, followed by diffusion in the quiescent liquid medium between primary particles to the stirred bulk aqueous medium. A reaction-diffusion model is proposed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.